President Donald Trump raised questions Wednesday night about a decades-old U.S. prohibition on testing its nuclear weapons by detonating them, a prospect which experts say is dangerous to populations and would open a door for adversaries to test and sharpen their most powerful weapons.

President Donald Trump's order for the Defense Department to start testing nuclear weapons could lead to billions of dollars' worth of contracts for a handful of specialized companies that dominate t...

The treaty, however, is due to expire in February 2026.